Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Bioenergy: how to measure the efficiency of different materials

  1. Feb 22, 2012 #1
    Hello all! I chose not to follow the given format, as my question is kind of unique. I hate to be one of those people who just create an account for one thread (as I usually try to avoid this), but my situation is quite urgent.

    I have a project due Friday, in which I plan to take different materials from where I live and measure there efficiency as biofuels. (different woods, plants, etc.).

    So, my questions are:

    1. What is a simple method in which I could measure the energy of different materials that I (basically) am going to find in my back yard (it doesn't necessarily have to be "scientific". If the only method of accomplishing this without a lab is to set it on fire and describe the flames, please do say so).

    2. If I can scientifically measure this, what units would I use?

    Thank you all in advanced. I'm really hesitant on whether I am actually going to do any of this, as the teacher most definitely wouldn't be trying something like this herself. I know this may sound dishonest of me, but I could rant for hours about some of the assignments she has assigned us : )

  2. jcsd
  3. Feb 23, 2012 #2


    User Avatar

    Staff: Mentor

    You are looking for a heat of combustion (check units in wikipedia), it requires a bomb calorimeter to be done properly.
  4. Feb 23, 2012 #3


    User Avatar
    Science Advisor
    2017 Award

    A rough way to do this measurement would be to burn the materials underneath a can of water and measure the temperature change of the water after burning. This could probably be done in a way that the results would reflect the relative energy density (e.g. energy per unit mass) of the different materials.
  5. Feb 23, 2012 #4
    That sounds like a possibility. Thanks!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook